Cooling of coke and obtaining a nitrogen hydrogen mixture



Patented May 15, 1934 EE STTS COOLING OF COKE AND OBTAINING NITROGEN HYDROGEN MIXTURE No Drawing. Application January 5, 1931, Serial No. 506,746. In Great Britain January 28,

6 Claims.

This invention relates to the production of a nitrogen hydrogen mixture suitable for ammonia synthesis as a by-product in the cooling of coke by means of water or steam. Processes are already known for cooling coke in which the hot coke is sprayed with water in a closed container and the resulting water gas is collected. In my co-pending application 9408/29 I have described an improved process for cooling coke in which hot coke is treated with Water in a closed system, the water being supplied to a bed of coke at a considerable depth, the steam thereby generated rising through the hotter zones of the coke bed, cooling the next higher layers and reacting in the upper layers to form water gas.

I have now found that by admitting air to a mass of coke while spraying the same with water or treating with water or treating with steam and collecting together the gases so produced it is possible to obtain a gaseous mixture composed of hydrogen, carbon monoxide, carbon dioxide, nitrogen and steam, from which, if the amount of air is suitably regulated, after conversion of carbon monoxide to its equivalent of hydrogen according to known methods, a nitrogen hydrogen mixture in the ratio of 1:3 can be obtained. It is preferred to pass the gas mixture from the coke cooling stage to the carbon monoxide conversion plant without intermediate condensation of the steam, the excess steam from the coke cooling operation serving for the carbon monoxide conversion.

According to a preferred form of my invention a large chamber is used capable of holding the charges from a battery of coke ovens. Each hot charge is fed in to the top of the cooling chamber, the cooling reaction being interrupted for the necessary interval, and the cooled coke is Withdrawn continuously from the bottom. The water spray is admitted at a depth where the coke has become cooled to a temperature of 550 C. and the air at a depth where the temperature is 900 C. By working in this manner the heat generated by combustion of coke in the oxygen of the air supplied is used in maintaining or raising the temperature of only that portion of the coke bed which is undergoing the water gas reaction, and thus the exit gases contain a higher percentage of Water gas.

Although susceptible of wide variation in the manner of operation the following example will serve to indicate how the invention may be practiced.

Example.-Coke at a temperature of 1000 C. was charged into a large cooling chamber of capacity 100 tons in quantities of 10 tons every 14 minutes. Water was sprayed in at a depth where the temperature was 550 C. at the rate of 10 tons per hour, and 3470 cubic metres of air were simultaneously admitted at a higher point where the temperature was 900 C. The resulting gas contained 4210 cubic metres of hydrogen, 4050 cubic metres of carbon monoxide, 820 cubic metres of carbon dioxide and 2760 cubic metres of nitrogen together with excess of steam. These gases were passed to the carbon monoxide conversion plant with the addition of excess steam as required, and as a result 11,000 cubic metres of a nitrogen hydrogen mixture were obtained in the ratio of 1:3. In this case 2.43 tons of coke per hour were consumed and the final temperature of the cooled coke was 200 C.

Various changes may be made in the method described without departing from the invention or sacrificing any of the advantages thereof.

I claim:

1. Process of cooling coke and producing a valuable gas therefrom which comprises spraying the coke with Water at a depth where the coke has become cooled causing the steam thus generated to rise through the coke and to meet air introduced at a higher level where the temperature is about 900 C.

2. Process of cooling freshly produced and hot coke and producing a valuable gas therefrom which comprises spraying said coke With water at a depth where the coke is at a temperature of about 550 C., introducing air at a depth where the temperature is about 900 C., adding steam, and converting the steam and carbon monoxide of the resulting gaseous mixture to carbon dioxide and hydrogen to yield a hydrogen-nitrogen mixture containing these gases in the ratio of approximately 3:1.

3. Process of cooling freshly produced and hot coke and producing a valuable gas therefrom which comprises spraying said coke with water, passing the thus generated steam thru the coke, introducing air at a higher level, and converting the steam and carbon monoxide of the resulting gaseous mixture to carbon dioxide and hydrogen to yield a hydrogen-nitrogen mixture containing these gases in the ratio of approximately 3:1.

4:. A process of cooling freshly produced and hot coke to a temperature of about 200 C. and producing a valuable gas therefrom which comprises spraying the coke with water at a depth where the temperature is about 550 C., introducing air into the coke bed at a depth where the temperature is about 900 C., adding steam and 6. Process of cooling coke and producing a valuable gas therefrom which comprises spraying coke with water at a depth where the coke has become cooled to a temperature of about 550 C., and introducing air at a depth where the temperature is about 900 C.

DANIEL TYRER. 

